Hair dryer

ABSTRACT

A hair dryer includes a motor and a fan to generate an air current within a housing, and a heater for selectively supplying heat into air introduced from the outside of the housing by the fan. A discharge nozzle is disposed on one end of the housing. A coanda surface is disposed on the discharge nozzle. Thus, the air passing through the housing flows along the coanda surface to suction air outside the discharge nozzle into a central passage part of the discharge nozzle, thereby mixing the suctioned air with the air passing through the housing. The air mixed within the central passage part is discharged through a discharge hole of the discharge nozzle. Since the air passing on the coanda surface suctions the air outside the discharge nozzle, the motor may be reduced in capacity. Also, an electromagnetic shielding effect may be significantly improved.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a hair dryer, and more particularly, toa hair dryer which generates an air current using a coanda effect.

2. Description of the Related Art

General hair dryers are devices in which an air current generated by afan driven by a motor is discharged to the outside to dry or adjustuser's hair. Air discharged from a hair dryer may be changed intemperature as occasion demands. Thus, to discharge air having arelatively high temperature, a heater may be provided within the hairdryer.

However, in the hair dryer according to the related art, an amount ofair discharged through a discharge hole is decided according to capacityof the motor and fan. Thus, to obtain a desired amount of air, each ofthe motor and fan should have capacity over a predetermined level. As aresult, the hair dryer may be relatively increased in size.

Also, when the motor is driven to rotate the fan, air suctioned from theoutside by the rotation of the fan passes through the heater and then isdischarged to the outside of the hair dryer. Thus, the heater isdisposed at a position adjacent to a portion through which the air isdischarged.

Thus, electromagnetic waves generated by the heater may be directlytransferred into the user's hair. Therefore, the electromagnetic wavesmay do harm to user's health.

In addition, since the heater is disposed adjacent to a discharge hole,water may be easily introduced through the discharge hole from theoutside. As a result, the water may contact the heater to electrocutethe user.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a hair dryer in whichan amount of air current generated by a fan rotated by an operation of amotor is increased by a coanda effect to transfer a relatively largeamount of air current into user's hair.

Another object of the present invention is to provide a hair dryer inwhich electrical components are disposed within the hair dryer away froma discharge hole corresponding to an upstream portion of an air flow toprevent moisture from being directly transferred into the electricalcomponents.

According to an aspect of the present invention, there is provided ahair dryer including: a housing defining an inner space therein, thehousing having an inflow slot, through which external air is introducedinto the inner space, in an outer surface of a side thereof; an aircurrent generation part disposed within the inner space of the housingto allow the external air introduced through the inflow slot from theoutside of the housing to pass through the housing; a heater disposedwithin the inner space to selectively supply heat into the air passingthrough the housing; and a discharge nozzle coupled to one end of thehousing, the discharge nozzle having a coanda surface on which the airpassing through the inside of the housing passes to suction the externalair by the air passing on the coanda surface, thereby discharging themixed air together.

A power source part supplying a power for operating the heater and theair current generation part are disposed on the other end of thehousing.

The air current generation part may include a motor and a fan rotated bythe motor to generate an air current.

The motor may be assembled with a motor housing fixed to the inner spaceof the housing.

The discharge nozzle may have a cylindrical shape of which at least oneportion has a circular shape and may include a central passage partrespectively having a secondary inflow hole passing through a centralportion thereof in front and rear directions to introduce the externalair and a discharge hole, in which the air passing through the housingand the external air are mixed with each other and are dischargedtherethrough, on both ends thereof.

A ring-shaped inner passage in which the air passing through the housingflows may be defined in the discharge nozzle, and a ring-shapeddischarge slit for discharging air onto the coanda surface may bedefined in a downstream portion of the inner passage.

An inner wall may define an inner surface of the discharge nozzle, andthe coanda surface for guiding the air discharged through the dischargeslit and a diffusion surface for gradually increasing a flow sectionalarea of the central passage part toward the discharge hole may becontinuously defined on the inner wall.

A coupling ring part having a screw part on an inner surface thereof maybe disposed on an outer surface of the discharge nozzle, and a screwpart corresponding to the screw part of the coupling ring part may bedisposed on an outer surface of the one end of the housing so that thedischarge nozzle is coupled to the one end of the housing.

The air current generation part may be disposed at an upstream portionof the air current flowing into the housing, and the heater may bedisposed at a downstream of the air current under the air currentgeneration part.

According to another aspect of the present invention, there is provideda hair dryer including: a housing defining an inner space therein, thehousing having an inflow slot, through which external air is introducedinto the inner space, in an outer surface of a side thereof; a motordisposed within the inner space of the housing, the motor rotating a fanfor generating an air current so that air is introduced from the outsideof the housing through the inflow slot to pass through the housing; aheater disposed within the inner space to selectively supply heat intothe air passing through the housing; and a discharge nozzle coupled toone end of the housing, the discharge nozzle having an inner passagethrough which the passing through the inside of the housing passes and acoanda surface for guiding the air discharged from the inner passage tosuction the external air by the air passing on the coanda surface,thereby discharging the mixed air together.

The discharge nozzle has a cylindrical shape of which at least oneportion may have a circular shape, an outer surface of the dischargenozzle may be defined as an outer wall, and an inner surface of thedischarge nozzle may be defined as an inner wall, an inner passage maybe defined between the outer wall and the inner wall to allow the airpassing through the housing to flow, a discharge slit through which theair passing through the inner passage is discharged may be disposedaround the inside of a rear end of the discharge nozzle to guide the aironto the coanda surface defined on the inner wall, and a central passagepart respectively having a secondary inflow hole passing through acentral portion of the discharge nozzle in front and rear directions tointroduce the external air and a discharge hole, in which the airpassing through the housing and the external air are mixed with eachother and are discharged the discharge nozzle, on both ends of thedischarge nozzle may be provided in the discharge nozzle.

The coanda surface for guiding the air discharged through the dischargeslit and a diffusion surface for gradually increasing a flow sectionalarea of the central passage part toward the discharge hole may becontinuously defined on the inner wall of the discharge nozzle.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 is a perspective view of a hair dryer according to an embodimentof the present invention;

FIG. 2 is a partial cross-sectional perspective view of an innerstructure of the hair dryer according to an embodiment of the presentinvention;

FIG. 3 is an exploded perspective view of a motor and a fan according toan embodiment of the present invention;

FIG. 4 is a detailed cross-sectional view of a discharge nozzleaccording to an embodiment of the present invention; and

FIG. 5 is an operation state view illustrating an air current generationprocess according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings.

Referring to the drawings, a housing 10 defines a portion of an outerappearance of a hair dryer. In the current embodiment, the housing 10has a cylindrical shape. Also, the housing 10 provides an inner space 11in which parts to be described below are installed. The housing 10 mayhave a polygonal shape such as a square shape or an oval shape incross-section.

A manipulation button 12 is disposed on a side of an outer surface ofthe housing 10. The manipulation button 12 manipulates an operation ofthe hair dryer. A plurality of inflow slots 14 is defined in a lowerportion of the housing 10. The plurality of inflow slots 14 may bedisposed side by side around a lower outer circumference of the housing10. The inflow slots 14 may serve as passage through which air isintroduced inward from the outside of the housing 10.

A power source part 16 is disposed on a lower end of the housing 10. Thepower source part 16 supplies a power for operating the hair dryer. Thepower source part 16 may be a portion in which a chargeable battery ordry cell is inserted, or a power line and plug connected to a powersource are disposed.

A motor housing 18 is disposed within the housing 10. An outer surfaceof the motor housing 18 may be closely attached to an inner surface ofthe housing 10. In the motor housing 18, inner inflow slots 18′ aredefined in positions corresponding to those of the inflow slots 14 tointroduce external air into the motor housing 18.

A motor 20 is disposed within the motor housing 18. The motor 20receives a power from the power source part 16 and then is driven toprovide a rotation force. A fan 22 is disposed on a rotation shaft (notshown) of the motor 20. The fan 22 is rotated inside the motor housing18 to introduce air from the outside of the housing 10 into the motorhousing 18 through the inflow slots 14 and the inner inflow slots 18′and then blow into a discharge nozzle 30 that will be described below.

The fan 22 is rotated inside the motor housing 18 so that the air flows.Also, the fan 22 is designed so that the fan 22 does not interfere withparts disposed on the inner surface of the motor housing 18 to guide theair flow. The motor housing 18, the motor 20, and the fan 22 may beprovided as one assembly. The assembly may be inserted into andassembled with the housing 10.

A cap 24 is disposed on an inner surface of an upper end of the housing10. The cap 24 includes a cap body 25 having a ring shape and aconnection bar 25′ crossing the cap body 25 in a diameter direction. Thecap 24 may be press-fitted into or screw-coupled to the inner surface ofthe housing 10 to fix parts disposed within the housing 10.

A plurality of fixing bars 26 are disposed between the cap 24 and themotor 20 to fix the motor 20 to the inside of the housing 10. In thecurrent embodiment, four fixing bars 26 may be provided. Here, if themotor housing 18 is firmly fixed to the inside of the housing 10, it maybe unnecessary to provide the cap 24 and the fixing bars 26.

A heater 28 is disposed on an inner upper end of the housing 10, i.e., aposition corresponding to an upper side of the motor 20. The heater 28includes a plurality of heating plates arranged side by side in a lengthdirection of the housing 10. Air may be heat-exchanged with the heatingplates while passing between the heating plates. The air passing throughthe heater receives heat and thus is increased in temperature. Theheater 28 receives a power from the power source part 16 to generateheat.

A discharge nozzle 30 is disposed on an upper end of the housing 10. Thedischarge nozzle 30 is configured to mix the air passing through thehousing 10 with the external air, thereby discharging the mixed air. Atleast one portion of the discharge nozzle 30 in cross-section has acircular shape. In the current embodiment, the discharge nozzle 30 hasan oval cylindrical shape in which the discharge nozzle 30 has an ovalshape in cross-section. However, the discharge nozzle 30 may have acircular shape in cross-section.

A coupling ring part 32 is disposed on a side of an outer surface of thedischarge nozzle 30. The coupling ring part 32 is coupled to the upperend of the housing 10. A screw part is disposed on an inner surface ofthe coupling ring part 32. That is, a screw part corresponding to anupper outer surface of the housing 10 may be disposed on an innersurface of the coupling ring part 32 to couple the discharge nozzle 30to the housing 10.

An inner passage 33 is defined within the discharge nozzle 30. The innerpassage 33 has a ring shape around the inside of the discharge nozzle30. The whole shape of the inner passage 33 may be is relevant to thatof the discharge nozzle 30. The inner passage 33 is a portion into whichthe air discharged from the housing 10 flows. Here, the coupling ringpart 32 may serve as an inlet of the inner passage 33.

An outer wall 34 and an inner wall 35 may be associated with each otherto define the inner passage 33. The outer wall 34 defines an outersurface of the discharge nozzle 30, and the inner wall 35 defines aninner surface of the discharge nozzle 30.

A predetermined section may be defined as a coanda surface 35′ at anupstream portion of air current discharged from the inner passage 33 inthe surface of the inner wall 35, i.e., a position getting out of adischarge slit 36 that will be described below. When a fluid flows, thefluid may flow along a surface of the coanda surface 35′. Thus, thecoanda surface 35′ may generate a coanda effect. Since the coanda effectis a previously known fact, its description will be omitted. A diffusionsurface 35″ connected to the coanda surface 35′ and disposed along theinner wall 35 is provided. The diffusion surface 35″ may be configuredso that the inner wall 35 is gradually increased in flow sectional area.

The discharge slit 36 is defined in a downstream portion of the innerpassage 33. The discharge slit 36 is defined around an inner surface ofa rear end of the discharge nozzle 30. That is, ends of the inner wall35 and the outer wall 34 are disposed adjacent to each other to define apredetermined gap therebetween, thereby defining the discharge slit 36.Thus, the discharge slit 36 may have a shape corresponding to that of across-section of the discharge nozzle 30. Air flowing along the innerpassage 33 is discharged through the discharge slit 36 to flow onto thecoanda surface 35′. The outer wall 34 defining the discharge slit 36 hasa semicircular shape in longitudinal section to provide a predeterminedgap between the outer wall 34 and a rear end of the inner wall 35. Thegap may serve as the discharge slit 36. Also, an amount of airdischarged through the discharge slit 36 may be decided according to awidth of the discharge and an angle of the coanda surface 35′. The outerwall 34 and the inner wall 36 may be designed in shape so that a flowsectional area from the inner passage 33 toward the discharge slit 36 isgradually decreased.

A central passage part 37 is disposed to pass through the inside of thedischarge nozzle 30 in front and rear directions. The coanda surface 35′and the diffusion surface 35″ which are portions of the surface of theinner wall 35 are defined on an inner surface of the central passagepart 37. Thus, the central passage part 37 may have a flow sectionalarea gradually increasing from a rear end of the discharge nozzle 30toward a front end.

The front end of the central passage part 37, i.e., a portion throughwhich air is finally discharged from the discharge nozzle 30 may bereferred to as a discharge hole 38, and the rear end of the centralpassage part 37, i.e., a portion through which air is introduced intothe central passage part 37 may be referred to as a secondary inflowhole 38′. Air may be introduced from the outside of the discharge nozzle30 through the secondary inflow hole 38′ by a low pressure region whichis generated while the air discharged through the discharge slit 36flows along the coanda surface 35′. The air introduced through thesecondary inflow hole 38′ is mixed with the air discharged through thedischarge slit 36 while passing through a region corresponding to thediffusion surface 35″, and then the mixed air is discharged through thedischarge hole 38.

Hereinafter, the assembly and use of the hair dryer including theabove-described components will be described in detail.

In the hair dryer according to the current embodiment, the power sourcepart 16 is mounted on the lower end of the housing 10. Thus, the lowerend of the housing 10 may be closed by the power source part 16 or aseparate structure. The motor housing 18 is inserted through the upperend of the housing 10. Here, the motor 20 and the fan 22 are previouslyassembled with the motor housing 18. That is, the motor housing 18, themotor 20, and the fan 22 are provided as one assembly. Due to theabove-described structure, external air may be suctioned into thehousing 10 to generate an air current passing through the inside of thehousing 10. Thus, the assembly may be called an air current generationpart.

After the motor 20 is inserted, the heater 28 is inserted into and fixedto the inner space 11 of the housing 10. The fixing bar 26 is insertedinto the inside of the upper end of the housing 10 in which the heater28 is inserted. Then, an end of the fixing bar 26 is seated on onesurface of the motor 20. Next, the cap 24 is press-fitted into and fixedto an inlet of the upper end of the housing 10 to prevent the partswithin the housing 10 from being randomly moved or separated from thehousing 10.

Next, the screw part disposed on the inner surface of the coupling ringpart 32 of the discharge nozzle 30 is coupled to a screw part disposedon the outer surface of the upper end of the housing 10. As a result,the discharge nozzle 30 is coupled to the housing 10, and also, theinside of the housing 10 communicates with the inner passage 33 of thedischarge nozzle 30.

To operate the hair dryer assembled as described above according to thecurrent embodiment, the manipulation button 12 should be manipulated bythe user. For example, the manipulation button 12 may be manipulated toselect one of a hot wind mode and a room-temperature wind mode. In caseof the hot wind mode, the heater 28 generates heat to heat the airdischarged from the discharge hole 38 at a predetermined temperature. Incase of the room-temperature wind mode, the heater 28 does not generateheat. Thus, the air suctioned into the housing 10 just passes throughthe heater 28 without being heat-exchanged with the heater 28. Thus, airhaving room temperature is discharged through the discharge hole 38.

The motor 20 may be driven to rotate the fan 22, thereby suctioning airinto the housing 10. An air current may be generated in a direction ofthe heater 28 within the housing 10 by the rotation of the fan 22. Theinner space 11 corresponding to the inside of the inflow slot 14 of thehousing 10 may have a relatively low pressure by the air current. Thus,air may be introduced as shown by an arrow i of FIG. 5 through theinflow slot 14 and the inner inflow slot 18′ from the outside of thehousing 10.

The air introduced into the housing 10 passes through the outside of thefan 22 and the motor 20 to pass between the heating plates of the heater28. In case of the hot wind mode, the air is heat-exchanged with theheating plates to increase a temperature of the air.

The air passing through the heater 28 passes through the coupling ringpart 32 to flow into the inner passage 33 as shown by an arrow e of FIG.5. The air introduced into the inner passage 33 is transferred into thewhole region of the inner passage 33 having the ring shape and then isdischarged from the inner passage 33 through the discharge slit 36.

The air discharged through the discharge slit 36 flows along the coandasurface 35′ as shown by an arrow A of FIG. 5. As described above, whenthe air is increased in velocity while flowing along the coanda surface35′, the surrounding of the coanda surface 35′ may be relativelydecreased in pressure. Thus, as shown by an arrow B of FIG. 5, airoutside the discharge nozzle 30 is introduced into the central passagepart 32 through the secondary inflow hole 38.

The external air introduced into the central passage part 32 through thesecondary inflow hole 38 and the air discharged through the dischargeslit 36 are mixed with each other while passing through the section ofthe central passage part 32 corresponding to the diffusion surface 35″.Then, the air is discharged through the discharge hole 39 and istransferred into the user's hair.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present invention. Thus,it is intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

For example, the motor 20 and the fan 22 for suctioning air into thehousing 10 may be varied in configuration. That is, the fan 22 may bedisposed under the motor 20. Also, the fan 22 may be variously changedin shape.

Also, it is not necessary to insert the motor into the housing 10 in thestate where the motor 20 is assembled with the motor housing 18. Forexample, the motor 20 may be directly mounted in the inner space 11 ofthe housing 10. In this case, a structure for fixing the motor 20 may beprovided on an inner surface of the inner space 11 of the housing 10.

Also, unlike the above-described embodiment, in the air currentgeneration part including the heater 28 and the motor 20, the heater 28may be disposed adjacent to the inflow slot 14. Also, the air currentgeneration part including the motor 20 may be disposed adjacent to thedischarge nozzle 30.

The hair dryer according to the present invention may obtain effects asfollows.

According to the present invention, the air supplied from the outside ofhe discharge nozzle by the coanda effect may be mixed with the airsuctioned into the hair dryer by the operation of the fan to increasethe total amount of air, thereby discharging the air to the outside ofthe hair dryer. Thus, when compared to the hair dryer according to therelated art, the hair dryer according to the present invention may usethe motor and fan having relatively low capacities under the same flowrate. Thus, the hair dryer may be miniaturized on the whole to reducethe manufacturing costs.

Also, since the passage in which the air discharged from the inside ofthe housing passes through the discharge nozzle is relatively long, andalso the discharge slit is vary narrow, waterproof performance of thehousing may be improved to prevent moisture from being introduced intothe housing and from being transferred into the electrical componentwithin the housing.

In addition, since the heater is disposed at the relatively upstreamportion of the air current in the discharge hole of the discharge nozzleto sufficiently cover the electromagnetic waves generated in the heater,the direct transmission of the electromagnetic waves into the user maybe minimized.

Also, since the parts such as the heater is disposed relatively awayfrom the discharge hole and structurally shielded from the outside toimprove the waterproof performance of the housing, noise shieldingperformance in addition to the waterproof performance may be improved.Furthermore, since the motor and fan are relatively miniaturized, thenoise may be reduced on the whole.

Also, the motor is relatively decreased in capacity, power consumptionmay be reduced. Thus, if a battery is used as a power source, a use timeof the hair dryer may be maintained above a predetermined time.Therefore, a portable hair dryer may be manufactured.

What is claimed is:
 1. A hair dryer comprising: a housing defining an inner space therein, the housing having an inflow slot, through which external air is introduced into the inner space, in an outer surface of a side thereof; an air current generation part disposed within the inner space of the housing to allow the external air introduced through the inflow slot from the outside of the housing to pass through the housing; a heater disposed within the inner space to selectively supply heat into the air passing through the housing; and a discharge nozzle coupled to one end of the housing, the discharge nozzle having a coanda surface on which the air passing through the inside of the housing passes to suction the external air by the air passing on the coanda surface, thereby discharging the mixed air together.
 2. The hair dryer of claim 1, wherein a power source part supplying a power for operating the heater and the air current generation part are disposed on the other end of the housing.
 3. The hair dryer of claim 2, wherein the air current generation part comprises a motor and a fan rotated by the motor to generate an air current.
 4. The hair dryer of claim 3, wherein the motor is assembled with a motor housing fixed to the inner space of the housing.
 5. The hair dryer of claim 1, wherein the discharge nozzle has a cylindrical shape of which at least one portion has a circular shape and comprises a central passage part respectively having a secondary inflow hole passing through a central portion thereof in front and rear directions to introduce the external air and a discharge hole, in which the air passing through the housing and the external air are mixed with each other and are discharged therethrough, on both ends thereof.
 6. The hair dryer of claim 5, wherein a ring-shaped inner passage in which the air passing through the housing flows is defined in the discharge nozzle, and a ring-shaped discharge slit for discharging air onto the coanda surface is defined in a downstream portion of the inner passage.
 7. The hair dryer of claim 6, wherein an inner wall defines an inner surface of the discharge nozzle, and the coanda surface for guiding the air discharged through the discharge slit and a diffusion surface for gradually increasing a flow sectional area of the central passage part toward the discharge hole are continuously defined on the inner wall.
 8. The hair dryer of claim 7, wherein a coupling ring part having a screw part on an inner surface thereof is disposed on an outer surface of the discharge nozzle, and a screw part corresponding to the screw part of the coupling ring part is disposed on an outer surface of the one end of the housing so that the discharge nozzle is coupled to the one end of the housing.
 9. The hair dryer of claim 8, wherein the air current generation part is disposed at an upstream portion of the air current flowing into the housing, and the heater is disposed at a downstream of the air current under the air current generation part.
 10. A hair dryer comprising: a housing defining an inner space therein, the housing having an inflow slot, through which external air is introduced into the inner space, in an outer surface of a side thereof; a motor disposed within the inner space of the housing, the motor rotating a fan for generating an air current so that air is introduced from the outside of the housing through the inflow slot to pass through the housing; a heater disposed within the inner space to selectively supply heat into the air passing through the housing; and a discharge nozzle coupled to one end of the housing, the discharge nozzle having an inner passage through which the passing through the inside of the housing passes and a coanda surface for guiding the air discharged from the inner passage to suction the external air by the air passing on the coanda surface, thereby discharging the mixed air together.
 11. The hair dryer of claim 10, wherein the discharge nozzle has a cylindrical shape of which at least one portion has a circular shape, an outer surface of the discharge nozzle is defined as an outer wall, and an inner surface of the discharge nozzle is defined as an inner wall, an inner passage is defined between the outer wall and the inner wall to allow the air passing through the housing to flow, a discharge slit through which the air passing through the inner passage is discharged is disposed around the inside of a rear end of the discharge nozzle to guide the air onto the coanda surface defined on the inner wall, and a central passage part respectively having a secondary inflow hole passing through a central portion of the discharge nozzle in front and rear directions to introduce the external air and a discharge hole, in which the air passing through the housing and the external air are mixed with each other and are discharged the discharge nozzle, on both ends of the discharge nozzle is provided in the discharge nozzle.
 12. The hair dryer of claim 11, wherein the coanda surface for guiding the air discharged through the discharge slit and a diffusion surface for gradually increasing a flow sectional area of the central passage part toward the discharge hole are continuously defined on the inner wall of the discharge nozzle.
 13. The hair dryer of claim 10, wherein the coanda surface for guiding the air discharged through the discharge slit and a diffusion surface for gradually increasing a flow sectional area of the central passage part toward the discharge hole are continuously defined on the inner wall of the discharge nozzle. 